Hydraulic and electronic braking system for autonomous braking

Abstract

A brake system for a motor vehicle includes a first control module coupled to a first hydraulic brake circuit and a second hydraulic brake circuit. The first control module is configured to control fluid pressure within both the first hydraulic brake circuit and the second hydraulic brake circuit. A second control module coupled to the first hydraulic brake circuit and the second hydraulic brake circuit, wherein the second control module is configured to control fluid pressure within both the first hydraulic brake circuit and the second hydraulic brake circuit independent of the first control module. The first control module is disposed in series with the second control module in the first hydraulic brake circuit and the second hydraulic brake circuit.

What is claimed is: 
     
       1. A brake system for a motor vehicle comprising:
 a first brake set and second brake set; 
 a first hydraulic brake circuit connected to the first brake set; 
 a second hydraulic brake circuit connected to the second brake set; 
 a first control module coupled to the first hydraulic brake circuit and the second hydraulic brake circuit, wherein the first control module is configured to control fluid pressure within both the first hydraulic brake circuit and the second hydraulic brake circuit; and 
 a second control module coupled to the first hydraulic brake circuit and the second hydraulic brake circuit, wherein the second control module is configured to control fluid pressure within both the first hydraulic brake circuit and the second hydraulic brake circuit independent of the first control module, wherein the first control module is disposed in series with the second control module in the first hydraulic brake circuit and the second hydraulic brake circuit. 
 
     
     
       2. The brake system for a motor vehicle as recited in  claim 1 , wherein the first brake control module includes a first hydraulic pump coupled to at least one of the first hydraulic circuit and the second hydraulic circuit and the second brake control module includes a second hydraulic pump coupled to at least one of the first hydraulic circuit and the second hydraulic circuit, wherein each of the first hydraulic pump and the second hydraulic pump are independently operable to control fluid pressure in each of the first hydraulic circuit and the second hydraulic circuit. 
     
     
       3. The brake system for a motor vehicle as recited in  claim 1 , including a logic unit configured for assessing an operating state of the braking system and activating a redundant braking action in response to detection of a predefined condition of the braking system. 
     
     
       4. The brake system for a motor vehicle as recited in  claim 1 , wherein each of the first brake set and the second brake set comprise a plurality of wheel brakes. 
     
     
       5. The brake system for a motor vehicle as recited in  claim 4 , wherein at least one of the wheel brakes includes an integrated parking brake electronically coupled to each of the first control module and the second control module such that the integrated parking brake is actuatable by both of the first control module and the second control module. 
     
     
       6. The brake system for a motor vehicle as recited in  claim 1 , wherein each of the first control module and the second control module include separate power and data inputs. 
     
     
       7. The brake system for a motor vehicle as recited in  claim 1 , wherein fluid pressure within each of the first hydraulic system and the second hydraulic system is controlled by only one of the first control module and the second control module. 
     
     
       8. The brake system for a motor vehicle as recited in  claim 7 , wherein a one of the first control module and the second control module not controlling pressure is open to fluid flow therethrough as controlled by the one of the first and second control modules controlling pressure. 
     
     
       9. The brake system for a motor vehicle as recited in  claim 1 , including a fluid reservoir in fluid communication with both the first hydraulic circuit and the second hydraulic circuit. 
     
     
       10. The brake system for a motor vehicle as recited in  claim 9 , wherein the second control module is downstream of the first control module in both the first hydraulic circuit and the second hydraulic circuit, and the first control module is disposed between the reservoir and the second control module. 
     
     
       11. The brake system for a motor vehicle as recited in  claim 10 , wherein brake pressure is actuatable by both the first control module and the second control module, the first control module draws brake fluid from a reservoir and pumps the brake fluid through the second control module, and the second control module draws brake fluid through the first control module and pumps brake fluid through at least one of the first and second brake circuits. 
     
     
       12. The brake system for a motor vehicle as recited in  claim 1 , wherein the one of the first control module and the second control module not actuating brake pressure operates as a pass through for the brake fluid. 
     
     
       13. The brake system for a motor vehicle as recited in  claim 1 , including a driver actuated braking mechanism configured to provide a braking signal communicated to each of the first control module and the second control module. 
     
     
       14. The brake system for a motor vehicle as recited in  claim 13 , wherein the driver actuated braking mechanism comprises a brake pedal and hydraulic master cylinder coupled to the first and second braking circuits. 
     
     
       15. A method of operating a vehicle braking system comprising:
 configuring a first control module coupled to a first hydraulic brake circuit and a second hydraulic brake circuit, wherein the first control module is configured to control fluid pressure within both the first hydraulic brake circuit and the second hydraulic brake circuit; configuring a second control module coupled to the first hydraulic brake circuit and the second hydraulic brake circuit, and the second control module is disposed in series with the first control module in the first hydraulic brake circuit and the second hydraulic brake circuit; and 
 controlling fluid pressure with one of the first control module and the second control module within both the first hydraulic brake circuit and the second hydraulic brake circuit independent of the other of the first control module and the second control module. 
 
     
     
       16. The method as recited in  claim 15 , including freely flowing brake fluid through the one of the first control module and the second control module not controlling fluid pressure within one of the first brake circuit and the second brake circuit. 
     
     
       17. The method as recited in  claim 15 , including controlling brake pressure with one of the first control module and the second control module such that when the first control module draws brake fluid from a reservoir and pumps the brake fluid through the second control module when controlling brake pressure, and the second control module draws brake fluid through the first control module and pumps brake fluid through at least one of the first and second brake circuits when controlling brake pressure. 
     
     
       18. The method as recited in  claim 15 , including assessing an operating state of the braking system with a logic unit and activating a redundant braking action in response to detection of a predefined condition of the braking system.